Inbred corn line PHT47

ABSTRACT

According to the invention, there is provided an inbred corn line, designated PHT47. This invention thus relates to the plants and seeds of inbred corn line PHT47 and to methods for producing a corn plant produced by crossing the inbred line PHT47 with itself or with another corn plant. This invention further relates to hybrid corn seeds and plants produced by crossing the inbred line PHT47 with another corn line or plant.

FIELD OF THE INVENTION

This invention is in the field of corn breeding, specifically relatingto an inbred corn line designated PHT47.

BACKGROUND OF THE INVENTION

The goal of plant breeding is to combine in a single variety or hybridvarious desirable traits. For field crops, these traits may includeresistance to diseases and insects, tolerance to heat and drought,reducing the time to crop maturity, greater yield, and better agronomicquality. With mechanical harvesting of many crops, uniformity of plantcharacteristics such as germination and stand establishment, growthrate, maturity, and plant and fruit height, is important.

Field crops are bred through techniques that take advantage of theplant's method of pollination. A plant is self-pollinated if pollen fromone flower is transferred to the same or another flower of the sameplant. A plant is cross-pollinated if the pollen comes from a flower ona different plant.

Plants that have been self-pollinated and selected for type for manygenerations become homozygous at almost all gene loci and produce auniform population of true breeding progeny. A cross between twohomozygous lines produces a uniform population of hybrid plants that maybe heterozygous for many gene loci. A cross of two plants eachheterozygous at a number of gene loci will produce a population ofhybrid plants that differ genetically and will not be uniform.

Corn plants (zea mays L.) can be bred by both self-pollination andcross-pollination techniques. Corn has separate male and female flowerson the same plant, located on the tassel and the ear, respectively.Natural pollination occurs in corn when wind blows pollen from thetassels to the silks that protrude from the tops of the incipient ears.

The development of corn hybrids requires the development of homozygousinbred lines, the crossing of these lines, and the evaluation of thecrosses. Pedigree breeding and recurrent selection breeding methods areused to develop inbred lines from breeding populations. Breedingprograms combine the genetic backgrounds from two or more inbred linesor various other broad-based sources into breeding pools from which newinbred lines are developed by selfing and selection of desiredphenotypes. The new inbreds are crossed with other inbred lines and thehybrids from these crosses are evaluated to determine which of thosehave commercial potential.

Pedigree breeding starts with the crossing of two genotypes, each ofwhich may have one or more desirable characteristics that is lacking inthe other or which complement the other. If the two original parents donot provide all of the desired characteristics, other sources can beincluded in the breeding population. In the pedigree method, superiorplants are selfed and selected in successive generations. In thesucceeding generations the heterozygous condition gives way tohomogeneous lines as a result of self-pollination and selection.Typically in the pedigree method of breeding five or more generations ofselfing and selection is practiced: F₁ -→F₂ ; F₃ ;F₃ --→F₄ ; F₄ --→F₅,etc.

Backcrossing can be used to improve an inbred line. Backcrossingtransfers a specific desirable trait from one inbred or source to aninbred that lacks that trait. This can be accomplished for example byfirst crossing a superior inbred (A) (recurrent parent) to a donorinbred (non-recurrent parent), which carries the appropriate gene(s) forthe trait in question. The progeny of this cross is then mated back tothe superior recurrent parent (A) followed by selection in the resultantprogeny for the desired trait to be transferred from the non-recurrentparent. After five or more backcross generations with selection for thedesired trait, the progeny will be heterozygous for loci controlling thecharacteristic being transferred, but will be like the superior parentfor most or almost all other genes. The last backcross generation wouldbe selfed to give pure breeding progeny for the gene(s) beingtransferred.

A single cross hybrid corn variety is the cross of two inbred lines,each of which has a genotype which complements the genotype of theother. The hybrid progeny of the first generation is designated F₁. Inthe development of hybrids only the F₁ hybrid plants are sought.Preferred F₁ hybrids are more vigorous than their inbred parents. Thishybrid vigor, or heterosis, can be manifested in many polygenic traits,including increased vegetative growth and increased yield.

The development of a hybrid corn variety involves three steps: (1) theselection of plants from various germplasm pools; (2) the selfing of theselected plants for several generations to produce a series of inbredlines, which, although different from each other, breed true and arehighly uniform; and (3) crossing the selected inbred lines withunrelated inbred lines to produce the hybrid progeny (F₁). During theinbreeding process in corn, the vigor of the lines decreases. Vigor isrestored when two unrelated inbred lines are crossed to produce thehybrid progeny (F₁). An important consequence of the homozygosity andhomogeneity of the inbred lines is that the hybrid between any twoinbreds will always be the same. Once the inbreds that give a superiorhybrid have been identified, the hybrid seed can be reproducedindefinitely as long as the homogeneity of the inbred parents ismaintained.

A single cross hybrid is produced when two inbred lines are crossed toproduce the F₁ progeny. A double cross hybrid is produced from fourinbred lines crossed in pairs (A×B and C×D) and then the two F₁ hybridsare crossed again (A×B)×(C×D). Much of the hybrid vigor exhibited by F₁hybrids is lost in the next generation (F₂). Consequently, seed fromhybrid varieties is not used for planting stock.

Corn is an important and valuable field crop. Thus, a continuing goal ofplant breeders is to develop high-yielding corn hybrids that areagronomically sound based on stable inbred lines. The reasons for thisgoal are obvious: to maximize the amount of grain produced with theinputs used and minimize susceptibility of the crop to environmentalstresses. To accomplish this goal, the corn breeder must select anddevelop superior inbred parental lines for producing hybrids. Thisrequires identification and selection of genetically unique individualswhich in a segregating population occur as the result of a combinationof crossover events plus the independent assortment of specificcombinations of alleles at many gene loci which results in specificgenotypes. Based on the number of segregating genes, the frequency ofoccurrence of an individual with a specific genotype is less than 1 in10,000. Thus, even if the entire genotype of the parents has beencharacterized and the desired genotype is known, only a few if anyindividuals having the desired genotype may be found in a large F₂ or S₀population. Typically, however, the genotype of neither the parents northe desired genotype is known in any detail.

At Pioneer Hi-Bred International, a typical corn research station has astaff of four, and 20 acres of breeding nursery. Those researchers plantthose 20 acres with 25,000 nursery rows, 15,000 yield test plots in10-15 yield test sites, and one or two disease-screening nurseries.Employing a temporary crew of 20 to 30 pollinators, the station makesabout 65,000 hand pollinations per growing season, and produces fromthree to ten new inbreds which are proposed for commercial use eachyear. Over the 32 Pioneer research stations in North America, thisamounts to from about 100 to 300 new inbreds proposed each year fromover 2,000,000 pollinations. Of those, less than 50 and more commonlyless than 30 are actually selected for commercial use.

SUMMARY OF THE INVENTION

According to the invention, there is provided a novel inbred corn line,designated PHT47. This invention thus relates to the seeds of inbredcorn line PHT47, to the plants of inbred corn line PHT47, and to methodsfor producing a corn plant produced by crossing the inbred line PHT47with itself or another corn line. This invention further relates tohybrid corn seeds and plants produced by crossing the inbred line PHT47with another corn line.

DEFINITIONS

In the description and examples that follow, a number of terms are usedherein. In order to provide a clear and consistent understanding of thespecification and claims, including the scope to be given such terms,the following definitions are provided. ABS is in absolute terms and %MN is percent of the mean for the experiments in which the inbred orhybrid was grown.

BAR PLT=BARREN PLANTS. The percent of plants per plot that were notbarren (lack ears).

BRT STK=BRITTLE STALKS. This is a measure of the stalk breakage near thetime of pollination, and is an indication of whether a hybrid or inbredwould snap or break near the time of flowering under severe winds. Dataare presented as percentage of plants that did not snap.

BU ACR=YIELD (BUSHELS/ACRE). Actual yield of the grain at harvest inbushels per acre adjusted to 15.5% moisture.

DRP EAR=DROPPED EARS. A measure of the number of dropped ears per plotand represents the percentage of plants that did not drop ears prior toharvest.

EAR HT=EAR HEIGHT. The ear height is a measure from the ground to thehighest placed developed ear node attachment and is measured in inches.

EAR SZ=EAR SIZE. A 1 to 9 visual rating of ear size. The higher therating the larger the ear size.

EST CNT=EARLY STAND COUNT. This is a measure of the stand establishmentin the spring and represents the number of plants that emerge on a perplot basis for the inbred or hybrid.

GDU SHD=GDU TO SHED. The number of growing degree units (GDUs) or heatunits required for an inbred line or hybrid to have approximately 50percent of the plants shedding pollen and is measured from the time ofplanting. Growing degree units are calculated by the Barger Method,where the heat units for a 24-hour period are: ##EQU1##

The highest maximum temperature used is 86° F. and the lowest minimumtemperature used is 50° F. For each inbred or hybrid it takes a certainnumber of GDUs to reach various stages of plant development.

GDU SLK=GDU TO SILK. The number of growing degree units required for aninbred line or hybrid to have approximately 50 percent of the plantswith silk emergence from time of planting. Growing degree units arecalculated by the Barger Method as given in GDU SHD definition.

GRN APP=GRAIN APPEARANCE. This is a 1 to 9 rating for the generalappearance of the shelled grain as it is harvested based on such factorsas the color of the harvested grain, any mold on the grain, and anycracked grain. High scores indicate good grain quality.

MST=HARVEST MOISTURE. The moisture is the actual percentage moisture ofthe grain at harvest.

PLT HT=PLANT HEIGHT. This is a measure of the height of the plant fromthe ground to the tip of the tassel in inches.

POL SC=POLLEN SCORE. A 1 to 9 visual rating indicating the amount ofpollen shed. The higher the score the more pollen shed.

POL WT=POLLEN WEIGHT. This is calculated by dry weight of tasselscollected as shedding commences minus dry weight from similar tasselsharvested after shedding is complete.

It should be understood that the inbred can, through routinemanipulation of cytoplasmic factors, be produced in a cytoplasmicmale-sterile form which is otherwise phenotypically identical to themale-fertile form.

PRM=PREDICTED RM. This trait, predicted relative maturity (RM), is basedon the harvest moisture of the grain. The relative maturity rating isbased on a known set of checks and utilizes standard linear regressionanalyses and is referred to as the Comparative Relative Maturity RatingSystem which is similar to the Minnesota Relative Maturity RatingSystem.

RT LDG=ROOT LODGING. Root lodging is the percentage of plants that donot root lodge; plants that lean from the vertical axis at anapproximately 30° angle or greater would be counted as root lodged.

SCT GRN=SCATTER GRAIN. A 1 to 9 visual rating indicating the amount ofscatter grain (lack of pollination or kernel abortion) on the ear. Thehigher the score the less scatter grain.

SDG VGR=SEEDLING VIGOR. This is the visual rating (1 to 9) of the amountof vegetative growth after emergence at the seedling stage(approximately five leaves). A higher score indicates better vigor.

SEL IND=SELECTION INDEX. The selection index gives a single measure ofthe hybrid's worth based on information for up to five traits. A cornbreeder may utilize his or her own set of traits for the selectionindex. One of the traits that is almost always included is yield. Theselection index data presented in the tables represent the mean valueaveraged across testing stations.

STA GRN=STAY GREEN. Stay green is the measure of plant health near thetime of black layer formation (physiological maturity). A high scoreindicates better late-season plant health.

STK CNT=NUMBER OF PLANTS. This is the final stand or number of plantsper plot.

STK LDG=STALK LODGING. This is the percentage of plants that did notstalk lodge (stalk breakage) as measured by either natural lodging orpushing the stalks and determining the percentage of plants that breakbelow the ear.

TAS BLS=TASSEL BLAST. A 1 to 9 visual rating was used to measure thedegree of blasting (necrosis due to heat stress) of the tassel at timeof flowering. A 1 would indicate a very high level of blasting at timeof flowering, while a 9 would have no tassel blasting.

TAS SZ=TASSEL SIZE. A 1 to 9 visual rating was used to indicate therelative size of the tassel. The higher the rating the larger thetassel.

TAS WT=TASSEL WEIGHT. This is the average weight of a tassel (grams)just prior to pollen shed.

TEX EAR=EAR TEXTURE. A 1 to 9 visual rating was used to indicate therelative hardness (smoothness of crown) of mature grain. A 1 would bevery soft (extreme dent) while a 9 would be very hard (flinty or verysmooth crown).

TILLER=TILLERS. A count of the number of tillers per plot that couldpossibly shed pollen was taken. Data is given as percentage of tillers:number of tillers per plot divided by number of plants per plot.

TST WT=TEST WEIGHT (UNADJUSTED). The measure of the weight of the grainin pounds for a given volume (bushel).

TST WTA=TEST WEIGHT ADJUSTED. The measure of the weight of the grain inpounds for a given volume (bushel) adjusted for percent moisture.

YLD=YIELD. It is the same as BU ACR ABS.

YLD SC=YIELD SCORE. A 1 to 9 visual rating was used to give a relativerating for yield based on plot ear piles. The higher the rating thegreater visual yield appearance.

MDM CPX=Maize Dwarf Mosaic Complex (MDMV=Maize Dwarf Mosaic Virus andMCDV-Maize Chlorotic Dwarf Virus): Visual rating (1-9 score) where a "1"is very susceptible and a "9" is very resistant.

SLF BLT=Southern Leaf Blight (Bipolaris maydis, Helminthosporiummaydis): Visual rating (1-9 score) where a "1" is very susceptible and a"9" is very resistant.

NLF BLT=Northern Leaf Blight (Exserohilum turcicum, H. turcicum): Visualrating (1-9 score) where a "1" is very susceptible and a "9" is veryresistant.

COM RST=Common Rust (Puccinia sorghi): Visual rating (1-9 score) where a"1" is very susceptible and a "9" is very resistant.

GLF SPT=Gray Leaf Spot (Cercospora zeae-maydis): Visual rating (1-9score) where a "1" is very susceptible and a "9" is very resistant.

STW WLT=Stewart's Wilt (Erwinia stewartii): Visual rating (1-9 score)where a "1" is very susceptible and a "9" is very resistant.

HD SMT=Head Smut (Sphacelotheca reiliana): Percentage of plants that didnot have infection.

EAR MLD=General Ear Mold: Visual rating (1-9 score) where a "1" is verysusceptible and a "9" is very resistant. This is based on overall ratingfor ear mold of mature ears without determining specific mold organism,and may not be predictive for a specific ear mold.

ECB DPE=Dropped ears due to European Corn Borer (Ostrinia nubilalis):Percentage of plants that did not drop ears under second brood cornborer infestation.

ECB 2SC=European Corn Borer Second Brood (Ostrinia nubilalis): Visualrating (1-9 score) of post flowering damage due to infestation byEuropean Corn Borer. A "1" is very susceptible and a "9" is veryresistant.

ECB 1LF=European Corn Borer First Brood (Ostrinia nubilalis): Visualrating (1-9 score) of preflowering leaf feeding by European Corn Borer.A "1" is very susceptible and a "9" is very resistant.

DETAILED DESCRIPTION OF THE INVENTION

Inbred corn line PHT47 is a yellow, dent corn inbred that is best suitedas a female in crosses for producing first generation F1 corn hybrids.PHT47 is best adapted to the North-Central part of the United States andcan be used to produce hybrids from approximately 110-125 relativematurity based on the Minnesota Relative Maturity Rating System forharvest moisture of grain. PHT47 yields well for its maturity, has goodgrain quality, and has good stalks and roots. The inbred tends to havepoor stay green and is white cobbed.

The inbred has shown uniformity and stability within the limits ofenvironmental influence for all the traits as described in the VarietyDescription Information (Table 1) that follows. Most of the data in theVariety Description information was collected at Johnston, Iowa. Theinbred has been self-pollinated and ear-rowed a sufficient number ofgenerations with careful attention paid to uniformity of plant type toensure homozygosity and phenotypic stability. The line has beenincreased both by hand and in isolated fields with continued observationfor uniformity. No variant traits have been observed or are expected inPHT47.

Inbred corn line PHT47, being substantially homozygous, can bereproduced by planting seeds of the line, growing the resulting cornplants under self-pollinating or sibpollinating conditions with adequateisolation, and harvesting the resulting seed, using techniques familiarto the agricultural arts.

                  TABLE 1                                                         ______________________________________                                        VARIETY DESCRIPTION INFORMATION                                               INBRED = PHT47                                                                ______________________________________                                        Type: Dent Region Best Adapted: Northcentral                                  A.  Maturity: Average across maturity zones. Zone: 0                              GDU Shed: 1520                                                                GDU Silk: 1530                                                                No. Reps: 70                                                              B.  Plant Characteristics:                                                        Plant height (to tassel tip): 232 cm                                          Length of top ear internode: 11 cm                                            Number of ears per stalk: Single                                              Ear height (to base of top ear): 76 cm                                        Number of tillers: None                                                       Cytoplasm type: Normal                                                    C.  Leaf:                                                                         Color: Dark Green (B14)                                                       Angle from Stalk: 30-60 degrees                                               Marginal Waves: Few (WF9)                                                     Number of Leaves (mature plants): 19                                          Sheath Pubescence: Light (W22)                                                Longitudinal Creases: Few (OH56A)                                             Length (Ear node leaf): 84 cm                                                 Width (widest point, ear node leaf): 9 cm                                 D.  Tassel:                                                                       Number lateral branches: 3                                                    Branch Angle from central spike: >45 degrees                                  Pollen Shed: Medium based on Pollen Yield Test                                (81% of experiment means)                                                     Peduncle Length (top leaf to basal branches): 21 cm                           Anther Color: Red                                                             Glume Color: Green                                                        E.  Ear (Husked Ear Data Except When Stated Otherwise):                           Length: 19 cm                                                                 Weight: 127 gm                                                                Mid-point Diameter: 41 mm                                                     Silk Color: Pink                                                              Husk Extension (Harvest stage): Medium (Barely covering                       ear)                                                                          Husk Leaf: Long (>15 cm)                                                      Taper of Ear: Slight                                                          Position of Shank (dry husks): Upright                                    Kernel Rows: Straight, Distinct                                                                      Number = 16                                                Husk Color (fresh): Light Green                                               Husk Color (dry): Buff                                                        Shank Length: 12 cm                                                           Shank (No. of internodes): 7                                              F.  Kernel (Dried):                                                               Size (from ear mid-point)                                                     Length: 11 mm                                                                 Width: 8 mm                                                                   Thick: 5 mm                                                                   Shape Grade (% rounds): 40-60 (56% medium round based                         on Parent Test Data)                                                          Pericarp Color: Colorless                                                     Aleurone Color: Homozygous Yellow                                             Endosperm Color: Yellow                                                       Endosperm Type: Normal Starch                                                 Gm Wt/100 Seeds (unsized): 30 gm                                          G.  Cob:                                                                          Diameter at mid-point: 25 mm                                                  Strength: Strong                                                              Color: White                                                              H.  Diseases:                                                                     Corn Lethal Necrosis (MCMV = Maize Chlorotic Mottle                           Virus and MDMV = Maize Dwarf Mosaic Virus):                                   Intermediate                                                                  Maize Dwarf Mosaic Complex (MDMV & MCDV = Maize                               Dwarf Virus): Susceptible                                                     Anthracnose Stalk Rot (C. graminicola): Intermediate                          S. Leaf Blight (B. maydis): Resistant                                         N. Leaf Blight (E. turcicum): Intermediate                                    Common Rust (P. sorghi): Resistant                                            Southern Rust (P. polysora): Intermediate                                     Eye Spot (C. zeae): Intermediate                                              Gray Leaf Spot (C. zeae): Susceptible                                         Stewart's Wilt (E. stewartii): Intermediate                                   Goss's Wilt (C. nebraskense): Resistant                                       Downy Mildew (P. sorghi): Resistant                                           Fusarium Ear Mold (F. moniliforme): Intermediate                          I.  Insects:                                                                      European Corn Borer-1 Leaf Damage (Pre-flowering):                            Susceptible                                                                   European Corn Borer-2 (Post-flowering): Susceptible                           The above descriptions are based on a scale of 1-9, 1 being                   highly susceptible, 9 being highly resistant.                                 S (Susceptible): Would generally represent a score of                         1-3.                                                                          I (Intermediate): Would generally represent a score of                        4-5.                                                                          R (Resistant): Would generally represent a score of 6-7.                      H (Highly Resistant): Would generally represent a score                       of 8-9. Highly resistant does not imply the inbred is immune.             J.  Variety Most Closely Resembling:                                          Character           Inbred                                                    Maturity            G39                                                       Usage               G39                                                       ______________________________________                                         In interpreting the foregoing color designations, reference may be had to     the Munsell Glossy Book of Color, a standard color reference.                 G39 (PVP Certificate No. 8300115) is a Pioneer HiBred International, Inc.     proprietary inbred.                                                           Data for Items B, C, D, E, F, and G is based primarily on a maximum of        eight reps from Johnston, Iowa grown in 1988, 1990 and 1991, plus             description information from the maintaining station.                    

ELECTROPHORESIS RESULTS Isozyme Genotypes for PHT47

Isozyme data were generated for inbred corn line PHT47 according to theprocedures described in Stuber, C.W., Wendle, J.F., Goodman, M.M., andSmith, J.S.C., "Techniques and Scoring Procedures for Starch GelElectrophoresis of Enzymes from Maize (Zea mays L.)," Technical BulletinNo. 286, North Carolina Agricultural Research Service, North CarolinaState University, Raleigh, N.C. (1988).

The data in Table 2 compares PHT47 with its parents, B47 and G39.

                  TABLE 2                                                         ______________________________________                                        ELECTROPHORESIS RESULTS FOR PHT47                                             AND ITS PARENTS B47 AND G39                                                                     PARENTS                                                     LOCI      PHT47         B47    G39                                            ______________________________________                                        ACP1      4             4      4                                              ADH1      4             4      4                                              CAT3      9             9      9                                              DIA1      8             12     8                                              GOT1      4             4      4                                              GOT2      2             4      2                                              GOT3      4             4      4                                              IDH1      4             4      4                                              IDH2      6             6      6                                              MDH1      6             6      6                                              MDH2      3.5           3.5    6                                              MDH3      16            16     16                                             MDH4      12            12     12                                             MDH5      12            12     12                                             MMM       4             4      4                                              PGM1      9             9      9                                              PGM2      4             4      4                                              PGD1      2             2      2                                              PGD2      5             5      5                                              PHI1      4             4      4                                              ______________________________________                                    

INDUSTRIAL APPLICABILITY

This invention also is directed to methods for producing a corn plant bycrossing a first parent corn plant with a second parent corn plantwherein the first or second parent corn plant is an inbred corn plantfrom the line PHT47. Further, both first and second parent corn plantscan come from the inbred corn line PHT47. Thus, any such methods usingthe inbred corn line PHT47 are part of this invention: selfing,backcrosses, hybrid production, crosses to populations, and the like.All plants produced using inbred corn line PHT47 as a parent are withinthe scope of this invention. Advantageously, the inbred corn line isused in crosses with other, different, corn inbreds to produce firstgeneration (F₁) corn hybrid seeds and plants with superiorcharacteristics.

As used herein, the term plant includes plant cells, plant protoplasts,plant cell tissue cultures from which corn plants can be regenerated,plant calli, plant clumps, and plant cells that are intact in plants orparts of plants, such as embryos, pollen, flowers, kernels, ears, cobs,leaves, husks, stalks, roots, root tips, anthers, silk and the like.

Duncan, Williams, Zehr, and Widholm, Planta, (1985) 165:322-332 reflectsthat 97% of the plants cultured which produced callus were capable ofplant regeneration. Subsequent experiments with both inbreds and hybridsproduced 91% regenerable callus which produced plants. In a furtherstudy in 1988, Songstad, Duncan & Widholm in Plant Cell Reports (1988),7:262-265 reports several media additions which enhance regenerabilityof callus of two inbred lines. Other published reports also indicatedthat "nontraditional" tissues are capable of producing somaticembryogenesis and plant regeneration. K.P. Rao, et al., Maize GeneticsCooperation Newsletter, 60:64-65 (1986), refers to somatic embryogenesisfrom glume callus cultures and B.V. Conger, et al., Plant Cell Reports,6:345-347 (1987) indicates somatic embryogenesis from the tissuecultures of maize leaf segments. Thus, it is clear from the literaturethat the state of the art is such that these methods of obtaining plantsare, and were, "conventional" in the sense that they are routinely usedand have a very high rate of success.

Tissue culture of corn is described in European Patent Application,publication 160,390, incorporated herein by reference. Corn tissueculture procedures are also described in Green and Rhodes, "PlantRegeneration in Tissue Culture of Maize," Maize for Biological Research(Plant Molecular Biology Association, Charlottesville, Virginia 1982, at367-372) and in Duncan, et al., "The Production of Callus Capable ofPlant Regeneration from Immature Embryos of Numerous Zea MaysGenotypes," 165 Planta 322-332 (1985). Thus, another aspect of thisinvention is to provide cells which upon growth and differentiationproduce corn plants having the physiological and morphologicalcharacteristics of the inbred line PHT47.

Corn is used as human food, livestock feed, and as raw material inindustry. The food uses of corn, in addition to human consumption ofcorn kernels, include both products of dry- and wet-milling industries.The principal products of corn dry milling are grits, meal and flour.The corn wet-milling industry can provide corn starch, corn syrups, anddextrose for food use. Corn oil is recovered from corn germ, which is aby-product of both dry- and wet-milling industries.

Corn, including both grain and non-grain portions of the plant, is alsoused extensively as livestock feed, primarily for beef cattle, dairycattle, hogs, and poultry.

Industrial uses of corn are mainly from corn starch in the wet-millingindustry and corn flour in the dry-milling industry. The industrialapplications of corn starch and flour are based on functionalproperties, such as viscosity, film formation, adhesive properties, andability to suspend particles. The corn starch and flour have applicationin the paper and textile industries. Other industrial uses includeapplications in adhesives, building materials, foundry binders, laundrystarches, explosives, oil-well muds, and other mining applications.

Plant parts other than the grain of corn are also used in industry.Stalks and husks are made into paper and wallboard and cobs are used forfuel and to make charcoal.

The seed of inbred corn line PHT47, the plant produced from the inbredseed, the hybrid corn plant produced from the crossing of the inbred,hybrid seed, and various parts of the hybrid corn plant can be utilizedfor human food, livestock feed, and as a raw material in industry.

EXAMPLE 3 INBRED PERFORMANCE OF PHT47

In the examples that follow, the traits and characteristics of inbredcorn line PHT47 are given as a line. The data collected on inbred cornline PHT47 is presented for the key characteristics and traits.

The results in Table 3A compare PHT47 to its B47 parent. The resultsshow PHT47 is lowering yielding and has a slightly higher test weightthan B47. PHT47 and B47 have similar plant height, but PHT47 hasslightly higher ear placement. PHT47 flowers (GDU Shed and GDU Silk)later than B47. PHT47 has better stay green and better resistance tostalk and root lodging than B47. PHT47 has slightly better Northern leafblight resistance, similar first brood European corn borer resistance,and better second brood European corn borer resistance compared to B47.

Table 3B compares PHT47 to its other parent, G39. PHT47 has higher yieldand test weight and lower grain harvest moisture than G39. PHT47 is ataller inbred with lower ear placement and flowers (GDU Shed and GDUSilk) earlier than G39. PHT47 has better grain appearance and rootlodging resistance, but similar stalk lodging resistance compared toG39. PHT47 has better resistance to ear mold, Northern leaf blight,Stewart's wilt, and second brood European corn borer, but is moresusceptible to common rust, Gray leaf spot, Southern leaf blight,Southern rust, and first brood European corn borer than G39.

                                      TABLE 3A                                    __________________________________________________________________________    PAIRED INBRED COMPARISON DATA                                                 VARIETY #1 = PHT47                                                            VARIETY #2 = B47                                                              __________________________________________________________________________                BU BU  YLD     EAR                                                                              BAR                                                                              PLT                                                                              EAR                                                                              SDG EST TIL                                    VAR ACR                                                                              ACR SC  MST SZ PLT                                                                              HT HT VGR CNT LER                            DEPT    #   ABS                                                                              % MN                                                                              ABS ABS ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS ABS ABS                            __________________________________________________________________________    TOTAL SUM                                                                             1   58.3                                                                             111 4.0 18.4                                                                              7.0                                                                              92.0                                                                             84.0                                                                             29.5                                                                             6.0 34.7                                                                              0.4                                    2   71.8                                                                             143 7.0 18.9                                                                              5.0                                                                              89.1                                                                             84.1                                                                             28.5                                                                             5.5 35.9                                                                              0.3                                    LOCS                                                                              3  3   1   3   1  3  2  2  3   7   3                                      REPS                                                                              12 12  1   11  1  11 7  6  10  36  7                                      DIFF                                                                              13.4                                                                             32  3.0 0.4 2.0                                                                              2.8                                                                              0.1                                                                              1.0                                                                              0.5 1.2 0.2                                    PROB                                                                              .289                                                                             .318    .085*  .478                                                                             .981                                                                             .376                                                                             580 .558                                                                              .423                           __________________________________________________________________________                GDU GDU TAS                                                                              TST                                                                              SCT STA STK RT  NLF                                                                              ECB                                                                              ECB                                   VAR SHD SLK SZ WT GRN GRN LDG LDG BLT                                                                              1LF                                                                              2SC                           DEPT    #   ABS ABS ABS                                                                              ABS                                                                              ABS ABS ABS ABS ABS                                                                              ABS                                                                              ABS                           __________________________________________________________________________    TOTAL SUM                                                                             1   1513                                                                              1503                                                                              6.0                                                                              58.7                                                                             3.0 7.0 98.9                                                                              98.2                                                                              7.0                                                                              4.0                                                                              6.0                                   2   1421                                                                              1412                                                                              7.0                                                                              57.4                                                                             8.0 5.6 96.2                                                                              42.4                                                                              6.0                                                                              4.0                                                                              3.5                                   LOCS                                                                              3   3   1  3  1   3   2   2   1  1  1                                     REPS                                                                              5   5   1  12 1   10  7   8   1  1  2                                     DIFF                                                                              92  91  1.0                                                                              1.3                                                                              5.0 1.4 2.7 55.8                                                                              1.0                                                                              0.0                                                                              2.5                                   PROB                                                                              .065*                                                                             .045+  .539   .039+                                                                             .180                                                                              .352                                    __________________________________________________________________________     * = 10% SIG                                                                   + = 5% SIG                                                                    # = 1% SIG                                                               

                                      TABLE 3B                                    __________________________________________________________________________    PAIRED INBRED COMPARISON DATA                                                 VARIETY #1 = PHT47                                                            VARIETY #2 = G39                                                              __________________________________________________________________________                 BU   BU   YLD      EAR BAR  PLT  EAR  SDG  EST DRP                       VAR  ACR  ACR  SC  MST  SZ  PLT  HT   HT   VGR  CNT EAR               DEPT    #    ABS  % MN ABS ABS  ABS ABS  ABS  ABS  ABS  ABS ABS               __________________________________________________________________________    TOTAL SUM                                                                             1    72.3 109  5.3 18.0 5.9 92.0 88.4 33.1 6.2  44.8                                                                              97.9                      2    53.4 79   4.4 19.0 5.4 78.3 84.0 35.7 5.7  45.6                                                                              99.0                      LOCS 40   40   15  46   12  49   35   35   43   67  16                        REPS 104  104  15  109  12  91   67   69   79   142 32                        DIFF 18.8 30   0.9 1.0  0.5 13.7 4.4  2.5  0.5  0.8 1.0                       PROB .000#                                                                              .000#                                                                              .100                                                                              .003#                                                                              .166                                                                              .000#                                                                              .000#                                                                              .000#                                                                              .035+                                                                              .168                                                                              .157              __________________________________________________________________________                 TIL                                                                              GDU  GDU POL  TAS                                                                              TAS TEX TST  GRN SCT  STA STK                        VAR  LER                                                                              SHD  SLK SC   BLS                                                                              SZ  EAR WT   APP GRN  GRN LDG                DEPT    #    ABS                                                                              ABS  ABS ABS  ABS                                                                              ABS ABS ABS  ABS ABS  ABS ABS                __________________________________________________________________________    TOTAL SUM                                                                             1    1.0                                                                              1533 1540                                                                              4.2  9.0                                                                              4.1 7.1 59.4 7.6 4.5  5.8 96.6                       2    0.4                                                                              1579 1613                                                                              5.8  9.0                                                                              5.7 5.9 57.6 6.7 4.3  6.0 96.0                       LOCS 32 51   46  13   1  18  9   40   24  14   32  31                         REPS 49 67   60  13   1  18  9   103  48  14   56  71                         DIFF 0.7                                                                              46   73  1.6  0.0                                                                              1.7 1.2 1.9  0.9 0.2  0.1 0.6                        PROB .085*                                                                            .000#                                                                              .000#                                                                             .002#   .000#                                                                             .016+                                                                             .000#                                                                              .012+                                                                             .512 .660                                                                              .431               __________________________________________________________________________                RT  BRT ANT                                                                              COM EAR GLF MDM NLF SLF SOU STW ECB ECB                        VAR LDG STK ROT                                                                              RST MLD SPT CPX BLT BLT RST WLT 1LF 2SC                DEPT    #   ABS ABS ABS                                                                              ABS ABS ABS ABS ABS ABS ABS ABS ABS ABS                __________________________________________________________________________    TOTAL SUM                                                                             1   99.3                                                                              100.0                                                                             3.5                                                                              7.0 6.1 1.9 3.0 4.2 5.6 5.0 5.3 3.5 5.8                        2   90.0                                                                              100.0                                                                             5.3                                                                              8.0 5.9 3.0 2.8 3.9 7.1 6.0 4.7 4.5 4.6                        LOCS                                                                              13  1   2  1   7   5   4   9   4   1   3   13  20                         REPS                                                                              37  2   3  1   7   9   8   12  7   1   3   13  40                         DIFF                                                                              9.3 0.0 1.8                                                                              1.0 0.3 1.1 0.3 0.3 1.5 1.0 0.7 0.9 1.2                        PROB                                                                              .046+   .395   .631                                                                              .029+                                                                             .495                                                                              .444                                                                              .014+   .184                                                                              .016+                                                                             .002#              __________________________________________________________________________     * = 10% SIG                                                                   + = 5% SIG                                                                    # = 1% SIG                                                               

Deposits

Applicants have made available to the public without restriction adeposit of at least 2500 seeds of inbred PHT47 with the American TypeCulture Collection (ATCC), Rockville, Md. 20852 USA, ATCC Deposit No.75610. The seeds deposited with the ATCC are taken from the same depositmaintained by Pioneer Hi-Bred International Inc., 700 Capital Square,400 Locust Street, Des Moines, Iowa 50309 since prior to the filing dateof this application. This deposit of the Inbred Corn Line PHT47 will bemaintained without restriction in the ATCC depository, which is a publicdepository, for a period of 30 years, or 5 years after the most recentrequest, or for the effective life of the patent, whichever is longer,and will be replaced if it becomes nonviable during that period.

What is claimed is:
 1. Inbred corn seed designated PHT47 and having ATCCAccession No.
 75610. 2. A corn plant produced by the seed of claim
 1. 3.A corn plant having physiological and morphological characteristics ofthe plant of claim
 2. 4. A corn plant having all the physiological andmorphological characteristics of the plant of claim 2, further havingcytoplasmic factors conferring male sterility.
 5. A tissue culture ofregenerable cells of a plant according to claim 2 wherein the tissueregenerates plants having all morphological and physiologicalcharacteristics of PHT47.
 6. Tissue culture of a plant according toclaim 5, the tissue culture selected from the group consisting ofleaves, pollen, embryos, roots, root tips, anthers, silk, flowers,kernels, ears, cobs, husks, stalks, cells and protoplasts thereof.
 7. Acorn plant regenerated from the tissue culture of claim 5 said plantpossessing all morphological and physiological characteristics of inbredPHT47.
 8. An F₁ hybrid seed and plant grown therefrom produced bycrossing an inbred corn plant according to claim 2 with another,different corn plant and having a genotype one half of which is thegenotype of the inbred corn plant of claim 2.